1. Field of the Invention
The present invention relates generally to the area of skateboards and, more particularly, to a skateboard truck assembly that substantially improves the board's stability and balance and enables a rider to more safely control the action of the skateboard when it shifts from a grinding maneuver to the dismount off the grind surface.
2. Description of the Prior Art
Skateboard truck assemblies in the prior art typically include a mounting plate, which connects the truck assembly to the underside of the skateboard, and some type of bracket to bridge the axle assembly and wheels to the mounting plate. The two axle assemblies on a skateboard are mostly conventional in design and include the axles and the wheels mounted to the axles. As disclosed in U.S. Pat. No. 4,898,398 to Cassel; U.S. Pat. No. 4,398,735, to Evans, et al., and U.S. Pat. No. 4,214,768 to Dominy, et al., axles generally tend to be straight, not bent or curved, and narrow relative to the diameter of the wheels which are mounted to them. There is a space that exists between the point where the wheel is mounted to the axle and the wheel tread, possibly as much as 11/2" or more. It is this area between where the axle and the wheel are joined and the wheel tread that has been the principal cause of some serious safety problems plaguing skateboard riders since the inception of the device and the sport's popularity.
The problem is specifically associated with the maneuver in the sport called grinding, which involves the "dumping" of a skateboard in motion onto a grind surface, such as a railing or the coping of a cement swimming pool, and then catching the grind surface along the underside of the axle and sliding or "grinding" along the grind surface until the maneuver is over and the rider and the board complete the dismount. The challenge for the rider is to ride the board along the grind surface for as long as possible moving the board laterally between the wheels in the process and then, while there is still sufficient speed, and in a controlled fashion, slide the board off the grind surface and complete the dismount off the grind surface to bring the skateboard and rider safely to the ground.
The problem confronting the rider in these situations is the abrupt contact that often occurs between the inside area of the wheel, which is that portion between where the axle joins the wheel and the wheel tread, and the grind surface during the grinding maneuvers and the dismount. What normally happens is that the grind surface will usually snag or get hung up on the inside edge of the wheel as the board moves laterally between the wheels causing the board to jerk suddenly and consequently the rider to lose his balance. Too often this results in a fall and possible serious injury to the rider. The faster the skateboard is going during the grind, the more forcefully the rider could be catapulted off the board when the grind surface catches the inside of the wheel.
The solution to this problem is to provide an axle that includes the structural component with the means to assist the rider in maintaining better balance and that functions to improve the board's stability and predictability through the various grinding maneuvers and the dismount. In this regard, the axle component of the present invention has a gradual arch shape allowing for the grind surface to move in and away from the central portion of the axle in a more controllable, predictable and generally safer manner than has ever been possible with the prior art devices. Furthermore, the axle at both ends conforms to the shape of the interior sidewall of the wheel and has an underside component with a surface that coincides substantially with the surface of the wheel tread. These closely adjacent surfaces enable the board, riding along its axles in a grinding maneuver, to easily, and in a controlled and predictable manner, smoothly slide off the grind surface during the dismount without the normal risk of an abrupt snag or a sudden jerky motion that could catapult the rider to the ground and cause him serious injury.